Mobile Phone Security: All You Need to Know

By Shahrum Gilani
Nov 6, 2018 10:01 AM PT

We rely on our phones to process and store reams of personal digital data. Our digital activities -- from checking bank balances to paying for a product with a tap of the screen, to sending friends and family messages over social media, to accessing work emails remotely -- have turned our phones into a goldmine of personal information.

How secure is your mobile device? It's easy to forget that your mobile phone is essentially a pocket-sized computer and that, just as with any device that can connect to the Internet, mobile phones are at risk of a cyberattack.

The good news is that mobile malware is still relatively uncommon, with the total rate of infections standing at 8 percent. Mobile malware is outnumbered by PC attacks 40-1, as mobiles operate on far more customized systems, and malware must be tailored to a specific system.

Securing your mobile phone should be a top priority, both for personal and business use.

Types of Mobile Malware

The types of mobile malware users may be exposed to are many and varying. Following are some examples:

Mobile spyware: This form of malicious software can infiltrate seemingly benign programs and secretly monitor your activity, record your location, and steal sensitive passwords. You may even have inadvertently granted an app access to harvest this information when you downloaded it.

Rooting malware: A particularly unsavory form of malware, these bugs gain root access to a compromised device in order to provide hackers with administrative privileges and access to users' files. Some rooting malware, such as Ztorg, are able to embed themselves into the system folders, so that even a factory reset won't be able to remove them.

Mobile banking Trojans: As mobile banking grows in popularity, an increasingly grave problem in the cybersecurity world is mobile banking viruses. In 2017, mobile banking Trojans
attacked close to 260,000 users across 164 countries. Attackers masquerade as a legitimate banking app to lure users into installing it, only to steal their credentials.

SMS malware: This form of malware will manipulate a mobile phone to send premium-rate text messages, often without the user noticing until they receive a shocking bill at the end of the month.

How Your Mobile Phone Can Get Infected

By far the most common way that your device may become infected is if you download a malicious app. Cybercriminals may pirate an existing app and list it on a third-party app store with hidden malware attached, so that users who download the app invite malicious software onto their devices.

Hackers also exploit known vulnerabilities in an operating system, which is why it is paramount that you keep your device up-to-date with the latest software.

The old-school method of sending a virus via fake emails can pose a threat to mobile phones as well, and this extends to suspicious texts. If you click a link on a fraudulent email or text, it probably will send you to a dummy site and automatically download malware onto your device.

Another way you might expose yourself to an attack is by connecting to a public WiFi hotspot. As public WiFi is usually unencrypted, attackers can intercept the data stream between the user and the access point. Known as a "man-in-the-middle attack," this can enable intruders to eavesdrop on any conversations carried out over the compromised network.

Android vs. iOS

Google's Android is the main target for malware, with a reported
19 million malware programs developed especially for Android. The reason for this is three-fold: Android's dominance of the global smartphone market; the inconsistency of updates to the Android operating system; and its relatively open system for the distribution of apps.

More Android phones to attack

Although the Apple logo may have become ubiquitous over the years, 85 percent of smartphone users worldwide have an Android phone. Big name brands such as Samsung, Huawei and HTC all run on Google's Android OS.

Frequency of OS updates

Android's updates are more fragmented. When Google releases an update to Android, it takes some time for consumers to receive it, unless they have a Google branded device, such as a Pixel.

Non-Google Android devices, however, are customized with different apps and services, depending on the device manufacturer and network carrier behind the phone. Each customized version rolls out Android updates at a different rate.

Openness of platform

Android has a more open and adaptable platform that renders it more vulnerable to cyberattacks than the Apple iOS. Users can download apps from third-party sources, which are not regulated by Google Play.

This is how the majority of the 10 million Android devices became infected by the Adware Hummingbad in 2016, although a variant of the malware subsequently was discovered on 20 apps in Google's official Play Store.

The so-called "walled garden" of Apple's App Store, on the other hand, means that all iPhone apps are heavily vetted by Apple before they can be listed in this centralized point of distribution.

iOS Weaknesses

Nevertheless, Apple's iOS is not entirely failsafe. The large-scale XCodeGhost attack that occurred in China in 2015 compromised more than 39 apps, including older versions of the popular WeChat app.

The hackers had infiltrated the App Store by offering a counterfeit version of Apple's XCode software to developers. They then were able to steal data and send fake alerts to compromised devices to trick users into revealing their information.

Jailbroken iPhones, in particular, are at risk of a malware attack, because they circumvent the security restrictions imposed by the App store. Users may wish to jailbreak their phones in order to gain access to free apps or those that are not available on the App Store. However, this opens them up to significant risks, and users may find they have accidentally downloaded a dangerous app.

The KeyRaider hack of 2015, for instance, compromised more than 225,000 Apple accounts by targeting jailbroken iPhones and iPads.

What Are the Signs of a Malware Attack on Your Phone?

If you contract a virus on your computer, it can be quite straightforward to spot that something has gone wrong. You'll probably see hundreds of irritating pop-ups or find that your computer starts to randomly and sporadically crash.

The signs of an infection on your mobile phone, however, may be harder to spot. You may have some malware lurking in the background and corrupting your phone without even realizing it.

Key signs to look for are if your device suddenly begins to operate more slowly, or your battery drains more rapidly than usual. Far more than an indication that you need a phone upgrade, a noticeable and sudden drop in performance could be a sign of an infection.

Another tell-tale sign to assess whether you may have a virus on your phone is if you see sudden spikes in your data usage. This could be a result of a virus running background tasks that you aren't aware of, or trying to access the Internet in order to transmit data from your phone.

Strange charges on your monthly bill also could be symptomatic of a virus, as some malware can make money from sending premium texts from your phone without you noticing. Be sure to review your bill routinely so you can catch any dangerous viruses early.

How to Remove Mobile Malware

If you suspect that your phone may have been compromised, what steps can you take to remove malicious software?

Let's first consider how to remove mobile malware from an Android phone.

You need to start by putting your phone into Safe Mode. You can do this by holding down the power off button until you're prompted to reboot your device to Safe Mode. The Safe Mode will disable all third-party apps, so if you find that your device then works smoothly, you can be confident that a virus is at the root of your problem.

Then go into your settings and to the apps folder. Scan for the app that you think might be the culprit, or for anything that you don't recall downloading. You can remove it manually by clicking the uninstall button.

Top Tip: Sometimes the uninstall button will be gray and won't respond when you tap on it, because the malicious app has granted itself administrator status. In that case, you need to go into the security settings and deactivate administrator rights for the malicious app in question. You then should be able to remove the app from the app list.

If you are still unable to remove the malicious software from your device, you will need to do a full factory reset. This can be achieved by going into your phone settings and erasing all data.

Be sure that you have backed up any important files before you do this, as you will not be able to retrieve your beloved photos and important contact list afterward.

How do you remove a virus from an iPhone?

As explained above, iOS malware is far rarer than Android malware, but attacks are still possible. Respectable apps may have had malicious code inserted in them by a hacker. Users who have jailbroken their phones may have inadvertently downloaded a malicious app.

The good news is that iOS' sandboxing structure, which restricts every app's access, prevents any malware from spreading to and corrupting other apps or the underlying operating system.

This means that it is quite simple to see which is the compromised app causing your phone to malfunction. You'll only have problems when the app in question is open.

First, see if there is a newer version of the app in the App Store, as the problem may have been identified and resolved in a new update. If not, you will need to outright remove the app from your device by uninstalling it.

If the virus is manifesting itself as a redirect to a spammy Web page, you'll also want to clear your Safari history and data.

Tips for Securing Your Mobile Phone

Of course, the most effective way to protect your phone from malware is to take preventative steps to reduce the likelihood of contracting an infection in the first place.

Following are our top tips for securing your mobile phone:

Be wary of public WiFi hotspots

Do not access any sensitive information through public WiFi, such as logging into your bank or checking sensitive work emails, as a hacker may be able to intercept your communication through a "man-in-the-middle" attack. It is far more secure to use a 3G or 4G instead, or to use a VPN.

Do not jailbreak or root your device

It may sound appealing to be able to download paid apps for free by jailbreaking your iPhone or rooting your Android, but this removes the protection from Apple and Google respectively. Proceed with caution if you do go down this route, or you may find yourself vulnerable to malicious apps.

Only download apps from the official app stores

Savvy hackers have been known to slip past the walled garden of the App Store and the security measures of Google Play Protect, but your chances of downloading a malicious app are far lower if you stick to the official app stores.

Update your operating system

Cybercriminals exploit vulnerabilities in operating systems to gain access to outdated smartphones. Be sure to install updates to your software as soon as a new version is released, to minimize this risk.

Encrypt your device

Encrypting your phone will scramble all files so that only you have access to them. You'll need to enter a PIN or password to decrypt your phone every time you want to use it.

Review your access permissions

Often when consumers download new apps they don't take the time to read the Terms & Conditions, or consider what data they are allowing the app to access.

In some cases, it may be useful to allow an app to access your location, such as a transport or weather app. But does the app need to know your location even when you're not using it? Review your app permissions in your privacy settings, and disable any consents that don't seem essential.

I hope that you found this article on mobile phone security useful -- and that you now know that protecting your device involves far more than just sticking a screen protector and case on it!

Shahrum Gilani is the founder of
HandsetExpert, a recommendation site for phones and tariffs. He is a graduate of the University of Cambridge and University College London, and has a doctorate in computer science. Gilani is a published author in the fields of imaging and vision.